*) Add a hook (insert_error_filter) to allow filters to re-insert
     themselves during processing of error responses. Enable mod_expires
     to use the new hook to include Expires headers in valid error
     responses. This addresses an RFC violation. It fixes PRs 19794,
     24884, and 25123. [Paul J. Reder]


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@102038 13f79535-47bb-0310-9956-ffa450edef68